Patent GB-150060-A (GB)
Title: Improvements in or relating to electric step-by-step signalling apparatus
IPC: G08C25/00
Filed: 1919-05-26
Abstract: 150,060. Kilburn, B. E. D., (Ford Instrument Co.). May 26, 1919. Order apparatus.-The transmitter comprises a number of switches which are closed successivelv with a snap-action by the continuous operation of a handle connected through a lost-motion device to the cam-shaft of the switches. A second camshaft is connected to the first through transfer mechanism of the Geneva-stop type and operates a second set of switches. The transmitter is provided with a recorder the aperture of which is closed by shutters when the transmitter is operated in either direction beyond the readings of the recorder. A push switch at the transmitter closes the circuit of a signal lamp at the receiver when the reading is changed, and this circuit is opened automatically when a shutter obscures the readings of the transmitter recorder. The receiver comprises two electric motors separately controlled by the two parts of the transmitter, and each motor comprises five electro-magnets, each of which has two coils oppositely wound to render the poles of like polarity. The field coils are energized two or three at a time to provide twenty positions for the armature shaft. Two segmental armatures are mounted upon a shaft and each armature is provided with a flange to increase its area at the central portion. The armatures are given opposite polarities by means of fixed magnetizing-coils and their shaft is damped by a fan. The poles may be given opposite polarities and the armatures like polarities. Transmitter. A cam-shaft 14, Fig. 3, carries a .counter-wheel 2 having tens and hundreds columns and is connected to a cam-shaft 15 which carries a counter-wheel 1 having thousands and ten thousands columns. The shaft 14 is given an intermittent motion from a continuously rotated shaft 59, Fig. 11, in order to provide a snap-action of the transmitter switches. The shaft 59 is provided with a head 60 to which a sleeve 58 is secured by a set-screw 61. Between the shaft 59 and sleeve 58 is placed a coiled spring 63, Figs. 10 and 11, the ends 63<1> of which pass through an opening in the sleeve 58 and engage the walls of a slot 64 in the mutilated gear-wheels 56, 57. The wheel 56 is provided with a recess only which registers with the space between the two teeth of the wheel 57, and these wheels engage a pinion 55 the alternate teeth of which are one-half the length of the pinion. The short teeth of the pinion engage only the recess in the wheel 56, and after the pinion 55 has been operated by the wheel 57 it is locked by two adjacent long teeth engaging the periphery of the wheel 56. The pinion 55 engages a wheel 54, Figs. 3, 10 and 11. on the shaft 14 which carries a ratchet-wheel 65 against which a roller 66, Fig. 5, is drawn by a spring 68. The shaft 14 is held by the roller 66 until the spring 63, Figs. 10 and 11, is sufficiently tensioned to overcome the action of the spring 68, Fig. 5, when the shaft 14 is given a rapid movement. A sleeve 36, Figs. 3 and 9, of insulating material, is mounted upon the shaft 14 and has segments cut out opposite pairs of contact-arms 27, 27<1>. The arms are provided with contacts 28, 29 and rollers 39, which are held against the sleeve 36 by a spring 38. The contacts 28 and 29 are adapted to engage adjustable contacts 30 and 32 when a cut-out portion of the sleeve is engaged by the arm 27 or 27<1>. The arms 27, 27<1> are mounted upon transverse conducting bars 17 - - 21. In the modification shown in Fig. 6, fixed contacts 85 and 86 are adapted to be engaged by a contact 87 mounted upon a bell-crank lever 88. The lever 88 is mounted upon a pin 90 carried by a bell-crank lever 89, one end of which carries a roller 92 engaging the cam-sleeve 36. Two levers 96 and 97 are mounted upon the pin 90 and are drawn against a pin 99 on the lever 88 by means of a spring 98. When the lever 89 is actuated by the cam-sleeve 36 the contact 87 engages the contact 85 or 86, while a further movement of the lever 89 causes the contact 87 to slide over its engaging contact. The pin 99 moves one of the arms 96, 97 to stress the spring 98 in order that the parts may return to their normal positions when an inoperative portion of the cam-sleeve 36 engages the roller 92. The shafts 14 and 15 are connected by a transfer mechanism consisting of a mutilated gear 42, Figs. 3 and 5, having teeth 44, 45, a disk 43 with a recess 48 registering with the space between the teeth 44, 45, a pinion 41 mounted upon a shaft 40 and provided with a full number of teeth on the side 41a gearing with the gear 42 and half the full number of teeth on the side 41<b> gearing with the disk 43, and a pinion 50 mounted on the shaft 40 and gearing with a toothed wheel 51. The gear 42 and disk 43 are secured to the counter-wbeel 2 and the wheel 51 is secured to the counter-wheel 1. The shaft 40 is operated intermittently by the gear 42 and pinion 41 and locked during its inoperative periods by the disk 43 engaging the space between the teeth on the side 41<b>. To obscure the numbers appearing before the opening in the plate 16, Fig. 3, when the range is below the minimum of 5,000 yards or above the maximum of 24,950 yards two shutters 70 and 71, with an opening 71a between them, are provided. The shutters are secured to a disk 72, Figs. 3 and 8, at one end and to a hub 73, Figs. 3 and 5, at the other end. The disk 72 gears with a pinion 74 loose upon the shaft 40. The pinion 74 engages mutilated gears such as 75 so that after a complete revolution of the counterwheel 1 the disk 72 is rotated through an angle to throw one of the shutters 70 or 71 in front of the opening in the plate 16. The pinion 74 is similar in construction to the pinion 41. The hub 73, secured to the shutters 70, 71, is engaged by a roller 77, Fig. 5, and is provided with a .notch 78 into which the roller 77 is drawn when neither of the shutters are in front of the opening in the plate 16. The roller 77 is carried upon a spring-controlled arm 81 upon which is mounted a contact 82, Figs. 5 and 17, which normally engages a fixed contact 83 connected to a signal lamp 20<a> through a push switch 23a. When one of the shutters 70, 71 obscures the readings of the indicator the switch 82, 83 is opened by the operation of the hub 73 upon the arm 81 and the circuit of the signal lamp 20<a> at the receiver is opened. Receiver. The indicator disks at the receiver are operated by independent motors, each of which comprises two circular plates 100, 101, Fig. 12, connected by a plurality of iron cores 102. Each core 102 is provided with two oppositely-wound magnetizing-coils 104, 105 between which is placed a plate 106, Figs. 12 and 13. Armatures 108 and 109, having segmental tops 110 equal in length to the distance between the outer edges of two adjacent pole-pieces and provided with flanges 111, are mounted upon a shaft 107 carrying an indicator disk. The ends 112, 113 of the cores 102 are enlarged to form pole-pieces having curved inner faces. The armatures 108, 109 are polarized by fixed coils 116, 117, and the movement of the shaft 107 is damped by a fan 120 enclosed in a chamber 121 which may be filled with liquid. By energizing the five cores 102 two or three at a time the shafts 107 will occupy twenty positions. Circuit connexions. The circuit connexions of the transmitter and receiver are shown on Fig. 17. A signal lamp 20a within the receiver casing is. connected across the mains 1<a>, 1<b> through a switch 82, 83, Figs. 5 and 17, and a push switch 23<a>. When the reading of the indicator is changed, the switch 23a is closed to energize the lamp 20<a>; but if one of the shutters 70, 71, Figs. 3 and 8, is before the opening in the plate 16 of the transmitter the switch 82, 83 is opened and the lamp 20a cannot be energized.